Potion Seller

Levels 1-4

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A resourceful and courageous goblin “inventor” named Grobnaz has obtained a large number of alchemy ingredients (via perfectly legal channels, of course) and is mixing them more or less at random, then trying to sell them to passing adventurers. You never know what you’re going to get.


These encounters take place on a street corner in a bustling city, probably in a part of town where goblins are welcome and street vendors are unregulated. Grobnaz has a large, bubbling cauldron and makeshift alembic behind him, and two goblin assistants, who stir the pot noisily. The smell changes with every new ingredient they add. The alembic appears to be malfunctioning. Grobnaz himself is wearing a box strapped to his chest that is filled with clinking vials and bottles of the potions and elixirs he has already made.


Grobnaz is calling out to passing pedestrians who look like adventurers, or who look like they have money, or both. He attempts to sell them potions for their adventures, and is very insistent. He speaks well enough to be understood, but too loudly. His pupils are dilated unevenly. Anyone who takes even a cursory look at the cauldron or attendants can tell they have no idea what they’re doing. Grobnaz is proud to announce that he has no idea what the potions do, but that he is charging about the half the cost of a potion of healing for each mystery bottle. In the last week, customers have gained the strength of a giant, become nearly-immune to fire, and also been severely poisoned, so it’s a real toss-up.

Grobnaz the potion seller is looking to learn the secrets of alchemy.



There are three main parties interested in Grobnaz’s street operation:

  • Grobnaz himself is hoping to learn the craft of alchemy by observing the effect of each combination (which he has painstakingly memorized) on those who drink it. He also wants to make some money in the process, but this is his secondary goal.
  • Passing adventurers want to get the best possible potion combination for the cheapest price. They also want to not die in the process of finding that deal.
  • The local alchemists’ guild wants to expand its hold on the local potion market and increase their own control of it. This means exposing Grobnaz for the menace that he is… but without actually getting him shut down. At least, not until they get what they want from the local authorities.

What do your player characters want? What are their best and worst qualities? What goals are they pursuing? Read through a few of the examples below, then choose the encounter that best suits your situation.

  • If you have player characters who are pious or helpful, or who like to defend the weak, run Encounter A. If, on the other hand, they are greedy or uncaring, run Encounter C.
  • If you have player characters who want to gain political or social favor with a local faction, run Encounter B. If you have player character who want to uphold certain vows, or to gain favor with their gods, run Encounter A.
  • If you have player characters who need information from or about a criminal element in the city, run Encounter C.
  • If the player characters are working to foil some kind of villainous plan, run Encounter A.
  • If the player characters are just looking to make a quick buck, you have two choices: run Encounter B for a combat-based opportunity, or run Encounter C for a skill-based opportunity.

Random Potion Table – Used in Each of the Encounters Below

Roll 1d20Potion Effect
1The potion is a perfectly brewed potion of poison.
2The target is subject to the effects of the confusion spell.
3The creature becomes strongly magnetic. All metal weapons and armor that are not being held or wielded within 30 feet are immediately drawn towards them at high speed. The creature must succeed on a DC 13 Dexterity saving throw at the start of each of its turns for 1 minute or take 4d6 piercing damage and be restrained until the end of its next turn.
4The creature’s hair and nails turn to ash, causing it to have disadvantage on all Charisma checks for 10 minutes, after which they are restored.
5The target turns into a frog as though it had failed a save against polymorph.
6Smoke starts pouring out of the target’s ears, blinding it for 1 minute.
7The creature sprouts gills and gains the ability to breathe water, but loses the ability to breathe air for 1 minute.
8The target can speak only Aquan for 1 minute and forgets all other languages.
9The target rises 10 feet directly upwards at the start of each of its turns for 1 minute and cannot stop. At the end of the minute, the target falls.
10The target belches a spectacular amount of vomit which corrodes the ground. All terrain within 10 feet of the drinker becomes difficult.
11The targets grow to massive proportions and flap wildly, causing all unsecured objects under 50 pounds to go flying from the wind.
12The target heals 1d6 hit points at the start of each of its turns for 1 minute. If it heals beyond its maximum hit points, it begins to suffocate as its own flesh begins to close its mouth, eyes, nose, and ears. The target can stop its own suffocation by taking damage and keeping its hit points below its maximum.
13The creature starts belching fire. At the beginning of each of its turns, it must create a 5 foot wide, 10 foot long line of fire, dealing 2d6 fire damage to any creature in the line. Each time this line is creature, the creature takes 1d6 fire damage.
14The creature becomes deafened and blinded but gains blindsight out to 30 feet for 1 minute.
15The creature grows claws for 1 minute, gaining a climbing speed equal to half their base movement speed.
16The creature gains the benefits of the invisibility spell.
17The creature swells up and turns blue. It gains 10 temporary hit points, and returns to normal when these temporary hit points are gone.
18The creature gains one additional action this turn, but takes 2d6 necrotic damage if they use it.
19The creature’s blood turns acidic for 1 minute. If they are damaged by a creature within 5 feet of them, that creature takes 1d4 acid damage.
20The creature gains immunity to all damage until the end of their next turn. When this effect ends, they gain 1 level of exhaustion.
The random potion table used in several encounters.

Encounter A

In this encounter, Grobnaz pushes a group of rookie adventurers into trying a mystery potion, with unpredictable (and perhaps gruesome) results.

Setting up this Encounter

This encounter involves a group of rookie adventurers. If you have player characters who are pious or helpful, make these rookies sympathetic and disappointed, not pathetic. Describe them as frustrated and worn-down.

If you have player characters looking to uphold vows or gain favor with the gods, make them angry and indignant instead. Either way, make your Grobnaz more menacing and villainous. Describe his as aggressive or pushy, and have him drool when he talks, or scrape his claws on his armor—something to make your players set their teeth on edge.

If your players are looking to foil a villainous plot, Grobnaz should have an obvious affiliation with the villain your characters are pursuing. This can be a piece of clothing, special marking or tattoo, or something about his speech, but the player characters should notice it easily. Depending on how much information you want to give your players, Grobnaz might offer information easily or hold it close.


As the party passes by, they can see and hear Grobnaz arguing with a group of rookie adventurers. There are as many of them as there are in your party, and they have similar (though not identical) roles. The group leader (name idea: Allen/Alina Stormtaker) is holding a handful of glass vials, each with a different color liquid. One is smoking ominously. Grobnaz is trying to get the rookies to try the potions right then and there, on the street. As the party watches, one of the rookies takes a vial of thick blue liquid from the leader and pops the cork, but hesitates—not sure if drinking it is a good idea.

If no one intervenes, the rookie drinks the potion. Roll once on the Potion Table to see what happens. If it’s a 16+, roll again until you get a bad effect.

No one passing by intervenes, though if something really bad happens, they may hide. Left to their own devices, Grobnaz’s party (him plus two lackeys) and the rookies will argue over the potion effect, fight to first bloodied, then both retreat. Remember that Grobnaz wants knowledge first and money second, so if he can push more rookies into drinking potions, he will. The rookies want their money back, but don’t want to pay too dearly for it.

Resolving this Encounter

When this encounter finishes, your players who are pious, helpful, or who want to defend the weak should have had a chance to demonstrate that. Depending on the tone of your game, you should either reward them for this (gold never hurt anybody, and a few of the mystery potions, gifted by whomever they helped, are a good reward at this level, too… for the brave) or punish them for this (in a game with a grim or dark tone, whomever they helped would distrust them and perhaps express ingratitude at their aid).

If your players wanted to uphold certain vows or gain favor with certain gods, you can reward them based on how well they did that during this encounter. A passerby explaining the party’s actions to a local religious order might results in some goodwill, aid, or prayers. You might even show direct mechanical favor from the gods (advantage, a spell slot recharge, or bless spell effect) if that’s the type of game you’re running.

For players looking to foil a villainous plot, getting involved here should move them decidedly towards or away from that goal, depending on how they performed. If you’d like them to move towards successfully foiling the villainous plot, have Grobnaz know a key piece of information, such as a name, meeting place, password, or item location, that he is happy to bargain with. If you’d like to move them away from foiling that plot, have Grobnaz or his lackeys report the party’s actions to a villain or lieutenant. Have your villain react to the party meddling in their plans by sending more lackeys after the party, or by moving or changing their operation to invalidate some information the party already has. (Remember to always make new clues available in that case: the lackeys know the new password, for example, or the old meeting place contains some kind of evidence that points towards the new one.)

Encounter B

In this encounter, a local city official tries to stop people from buying Grobnaz’s potions. They might also employ the player characters to slay a dangerous magical beast that they say Grobnaz freed during his burglary.

Setting up this Encounter

This encounter involves a local trade or government official. If there is a local group your players want to gain favor with, such as a trade guild or local militia, make this official belong to that group. If not, a good default option is to have this person represent the local steward or chancellor—someone without a lot of military power, who might outsource some violence to adventurers looking to make a quick buck.

You should decide ahead of time how the Spellcrazed Manticore in the warehouse got there: did Grobnaz really free it during his burglary? Why is it there in the first place? And why hasn’t the guild gotten the local authorities involved about the theft? It must have something to do with the dangerous magical beast trapped in the warehouse. Attach your explanation to an existing faction (especially a criminal one) to send your players in that direction.


As the party passes by, they see Grobnaz calling out to adventurers and asking if they’ll buy his mystery potions. He makes some wild claims about what the potions are capable of, and his lackeys behind him nod and grunt along. A distraught-looking city official (name ideas: Tylas/Tylin Montabrogue) in a neat cloak that has been stained with flecks of potion-froth paces back and forth in front of Grobnaz, muttering inaudibly. Whenever Grobnaz gets too pushy, the official tries to shoo him away from the pedestrians, but Grobnaz bears his teeth and the official backs off.

As the party gets close enough to do or say anything, the official sees them and hurries over. Wringing their hands, the city official explains that the ingredients that Grobnaz is making his mystery potions from are stolen from a local alchemist guild and he is making unlicensed potions—and breaking many city ordnances in the process. The city official is warning all potential customers that the potions are dangerous.

If the party is interested in the potions, the city official won’t stop them, but will report their activity to the guild or whatever other local faction they represent. If the party is interested in helping, or offers to do something about Grobnaz, the city official hesitates.

Remember that the official doesn’t actually want Grobnaz to be shut down—just exposed for being dangerous. Have the official take a hard line on this. If the party wants to help, have the official offer them a different job instead: when Grobnaz broke into the warehouse and stole the ingredients, he let a dangerous magical beast loose. The beast is now in the warehouse, snacking on the left behind potion ingredients. The warehouse is only one street over, and the guild wants it taken care of quietly (or the city doesn’t want to risk its own manpower).

In that case, the beast can be found in the warehouse. If the party doesn’t go after it, have another adventuring party take the job in the next hour or so—the city official is persistent. It’s up to you if that group succeeds or not.

If the party decides to go to the warehouse: This warehouse is littered with the scraps of broken boxes and crates, and there is a pile of potion ingredients in the middle of the floor. The only creature inside is the Spellcrazed Manticore. It is busy eating ingredients, and will defend the pile of ingredients until it is bloodied, at which point it flees into the city and attempts to hide and heal near a source of magical energy.

As an action, a creature may consume up to 5 ingredients, taking 1d6 poison damage for each one consumed. The creature may then roll on the Potion Table as many times as potions they consumed, taking the highest result. While a creature is under the effects of such a potion, the Spellcrazed Manticore may target the creature with its Magical Feeding feature. The Spellcrazed Manticore itself can eat the ingredients without any effect—it just likes the way they taste.

Resolving this Encounter

Player characters who wanted to gain favor with a local faction should have taken advantage of the opportunity to do so here, but each faction might react differently. The alchemist’s guild will be grateful if the party managed to slay the Spellcrazed manticore, but not if the word got out, and especially not if the beast got loose in the city. On the other hand, the local authorities and city watch would be grateful for that information, and less happy if it were concealed from them. Consider how your factions would feel about the party’s actions. Consequences go both ways: a pleased faction might reward player characters with access to materials, craftsmen, discounts, or information. A displeased faction might leverage their economic power to raise prices for the PCs, or their local authority to harass or intimidate the characters.

Player character who just wanted to make a quick buck certainly have the chance to do that here. If they manage to slay the beast and it doesn’t escape into the city, have the city official reward them with a level-appropriate treasure hoard (with standard rules, about 350gp worth of coins, or about 275gp and a 2nd-level spell scroll, or 250gp and a small gold bracelet worth 25gp and a 2nd-level spell scroll). On the other hand, if the beast isn’t slain or manages to escape, the player characters should suffer negative consequences with the faction, as above.

Suggested city official stat block. D&D 5e SRD.

Encounter C

In this encounter, a disgruntled customer meets Grobnaz on the street and attacks him, sending potions and magical brew flying everywhere.

Suggested disgruntled customer stat block. D&D 5e SRD.

Setting up this Encounter

This encounter involves a disgruntled customer, which gives us some flexibility. If your player characters are interested in the criminal elements of the city (for any reason), have this disgruntled customer be a member of the organization they’re interested in, and make that affiliation obvious. Otherwise, such as if the PCs just want to make a quick buck, have that disgruntled customer be a powerful but aging adventurer.


As the party passes by, they notice a disgruntled customer (name ideas: Braden/Braith Darkdust) stalk out of a nearby tavern and interrupt Grobnaz while he is trying to sell to a pair of pedestrians. The disgruntled customer pushes the pedestrians out of the way and gets aggressive, shouting and shoving Grobnaz. The lackeys stop stirring the pot and reach for weapons. Have the disgruntled customer shout at Grobnaz about looking like a fool in front of some others, and describe an embarrassing potion effect.

When the disgruntled customer sees the lackeys reaching for weapons, they push Grobnaz hard, towards the cauldron. If the party wants to get involved earlier, have the push happen earlier—it’s important. As the disgruntled customer draws a weapon and engages with the lackeys on the street—fighting to first bloodied, not to the death—Grobnaz trips backwards and falls. The box of wares he has shatters and potions go everywhere—describe them rolling and bouncing over the cobblestones, cracks forming in glass with foul liquid seeping out, have smoke and colors and flahses—describe complete chaos. The potions are all over the street and can be scooped up easily, but Grobnaz will notice.

On Initiative count 20, losing ties, the cauldron spits out massive bursts of magic energy. All creatures within 10 feet is subject to a random potion effect from the Potion Table (each creature receives the same effect). A creature can drag the cauldron, but when doing so expends 2 feet of movement for every 1 foot moved.

As your players navigate this chaos, remember that Grobnaz wants to find out what the potions do more than he wants to make money. He’ll value the potions first, but if he can get a player character to drink one, he’ll try. The disgruntled customer wants their money back, but mostly wants to take their frustration out on Grobnaz. If the lackeys are bloodied and flee, the disgruntled customer will sheathe their weapon and attack Grobnaz (who is mostly unarmed now without the potions) with unarmed strikes until he is reduced to zero hit points (unconscious), then empty the cauldron on him and walk away. Depending on which organization (if any) the disgruntled customer belongs to, have them react to player character involvement appropriately (appreciating the help, offering information or a favor, or with vengeance after the players aid Grobnaz, or steal potions and don’t offer any aid).

Resolving this Encounter

For player characters interested in the criminal elements of the city, the disgruntled customer is a great resource. If the PCs managed to help out, have your disgruntled customer have access to a person or location that the party needs to pursue their criminal interest. The disgruntled customer isn’t all that principled, so they’re willing to give information to authorities or aid an investigation, though an extra bribe might be helpful.

On the other hand, if the party interfered with the disgruntled customer’s revenge, that’s a problem. Have your disgruntled customer complain about the party to their contacts, so informants and other people affiliated with the criminal organization will turn them away. You might even have the disgruntled customer come back and confront the party in the same way as they did Grobnaz—they love revenge, after all.

Parties who just want to make a quick buck likely stuffed their pockets with the mystery potions and even ingredients scattered all over the street. The local alchemist’s guild will buy these back at a premium, to cover up the embarrassment of having been burgled in the first place. Just have a representative approach the party in a quiet or private place to make the offer. If the party is actively looking for a buyer, have the guild representative find them before they get too loud about it. Each potion or handful of ingredients should sell for 1d4x10gp. You can cap your party’s rewards by saying that some of the potions they gathered are damaged or useless. You probably shouldn’t reward for more than a dozen potions at this level.